Rain This Weekend Could Make March Our Wettest On Record In W. Wash.

Mar 28, 2014

Friday's steady rain is contributing to what may become a record-breaking March for total rainfall in many places in the Northwest.

KPLU weather expert Cliff Mass says a wet front is coming through western Washington.

Showers, Clouds And Chance Of Heavy Thunderstorms

“A lot of people will get half an inch or maybe a bit less today [Friday afternoon]," said Mass, who teaches atmospheric sciences at the University of Washington. 

On Friday, "we’ll have some partly cloudy skies and some showers,” Mass said, predicting a short break from the precipitation Saturday morning, but expecting it to resume between 10 a.m. and noon, when an upper-level trough comes through.

“This will bring another increase of showers, and there’ll be some heavy thunderstorms and convective showers later in the afternoon and Saturday evening,” he said.

Pressure To Lift On Sunday

Then on Sunday, it looks like a weak high pressure area will be moving over the region.

“So we’ll have some showers, maybe a Puget Sound convergence zone north of Seattle and some showers in the mountains,” Mass said.

The freezing level will remain at about 4,000 feet, Mass said, so there will be snow at higher elevations, bringing fresh powder in some places, and “probably mixed rain and snow at the lower passes.”     

Then next week, Mass says there will be “a little break on Monday and more showers later on.

Record-Breaking March?

Mass says the big question for meteorologists right now is whether the rain through the end of this month will result in a new record for total precipitation.

“That’s what we’re all watching,” he said. At SeaTac, the all-time March record is 8.4 inches.

“Right now, this last hour (8 to 9 a.m. Friday), we were at 8.27. So I think we have a really good shot of breaking the all-time record," he said. 

In any case, the professor says it’s "amazing" to see things this wet in March.

“We’ll end up being like 4 inches or more above normal,” he said, adding that it’s not just SeaTac, but also other weather stations all over the map in western Washington that will be reaching their all-time March records.

Tragic Weather For Oso 

Included in those are areas of the North Cascades, such as the site of the deadly landslide at Oso, where the rain levels have already reached as much as 300 percent or 12 inches more rain than normal, contributing to the danger of landslides and hampering recovery efforts.

"So we've had an extraordinarily wet period, and this is of course contributing to a large number of slope failures, the most important one being the one in Oso," Mass said. 


The weekly KPLU feature "Weather with Cliff Mass" airs every Friday at 9 a.m. immediately following BirdNote, and twice on Friday afternoons during All Things Considered. The feature is hosted by KPLU Environment Reporter Bellamy Pailthorp. Cliff Mass is a University of Washington Professor of Atmospheric Sciences, a renowned Seattle weather prognosticator, and a popular weather blogger. You can also subscribe to a podcast of “Weather with Cliff Mass” shows.